Note: Descriptions are shown in the official language in which they were submitted.
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"ROCKING STATION FOR TREATMENT PLANT CONVEYANCE SYSTEMS"
The present invention relates to a rocking station to be
used in treatment plant conveyance systems, for example for
sheet metal frameworks such as motor vehicle chassis.
In the prior art rocking stations used when it is necessary
to swing objects being processed around one of the main
axes to perform technological operations such as for exam-
ple spraying fluids or scavenging liquids from pockets,
shallow water et cetera are known.
For example in the engineering of treatment by means of
fluids of the surfaces of frameworks made of sheet metal in
certain steps it is necessary to change the distance and
direction of fluid streams with respect to the surfaces
being treated or after a typical dipping treatment in a vat
or spraying it is necessary to scavenge the liquids
remaining trapped in the framework by swinging it.
Usually the frameworks being processed advance while
supported on a frame or base board termed 'skid' which can
be provided with two sleds applied each to the framework or
an actual frame in the shape of a sled on which is the
framework constrained.
The rocking movement can be achieved in various ways.
For example the board can be swung alternately around end
axes transversal to the travel direction or the board can
be swung around a central axis transversal to the travel
direction.
To achieve alternate rocking around the end axes of the
board various solutions, all relatively complicated, have
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been proposed in the prior art. For example stations
powered to lift the center and two controlled bolts, one at
each end, or release of one of the bolts allowing lifting
of the corresponding board end have been proposed. Stations
with two independent power sources, one for each board end
or with a single power source equipped with an engagement
and disengagement mechanism allowing alternate powering at
the two ends have also been proposed.
All these solutions are relatively complicated and cumber-
some and generally require relatively complicated
management.
The general purpose of the present invention is to remedy
the above mentioned shortcomings by making available a
rocking station with simple and reliable structure, reduced
space occupied and simple management.
In view of this purpose it was sought to provide in accor-
dance with the present invention a rocking station compris-
ing a frame in which there is a powered rocking board onto
which are fed objects to be rocked characterized in that
the board rests on the floor on supports arranged near its
two opposite ends with the supports defining two parallel
rotation axes of the board and each one near one of said
opposite ends and transversal to the board with there being
on each side of the board a chain defining two main lifting
branches with each main branch arranged between one part of
the frame above the board and couplings to the board
arranged near one of said opposite ends of the board with a
motor causing the chains to run on command in one or the
other direction to alternately place under tension one or
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the other main branch and lift the corresponding board end
by rotating the board around the rotation axis near the
opposite end.
To clarify the explanation of the innovative principles of
the present invention and its advantages compared with the
prior art there is described below with the aid of the
annexed drawings a possible embodiment thereof by way of
non-limiting example applying said principles. In the
drawings:
- FIG 1 shows a diagrammatic side elevation view of a
station in accordance with the present invention,
- FIG 2 shows a plan view of the station of FIG 1,
- FIG 3 shows a cross section view along plane of cut III-
III of FIG 1, and
- FIG 4 shows a diagrammatic view of a rocking movement of
the station.
With reference to the figures, FIG 1 shows a rocking
station designated as a whole by reference number 10 to
which tables 11 for support and transport of objects 12 are
fed sequentially in the direction indicated by the arrow 13
by known conveyance system means not shown. The object 12,
for example a motor vehicle framework, is constrained to
the board by known means not further shown nor described
because readily imaginable to those skilled in the art.
The station comprises a trestle 17 in which is a rocking
board 14 on which runs and rests the conveyance table 11
which enters the station. For moving the conveyance table
in the station the rocking board is equipped with transver-
sal rollers 15 powered synchronously by a motor 16. In
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this manner when a table 11 enters the station it is taken
over by the station conveyance system made up of the
powered rollers 15.
The station conveyance system is made in such a manner as
to prevent accidental running of the board received in the
station.
The board 14 has a pair of supports 18, 19 arranged symmet-
rically near the head and tail ends of the board to allow
support of the board on appropriate saddle shaped supports
20, 21 fastened on the floor. The supports define rotation
axes transversal to the board in such a manner that the
board can tilt while rotating around one support or the
other as clarified below.
Near the supports the board is equipped with idling pulleys
22, 23 for a pair of chains 24 arranged at the sides of the
board 14. Advantageously the rotation axis of the pulleys
coincides virtually with the rotation axes of the board on
the respective supports. The pulleys 22, 23 make couplings
of the chains to the rocking board to lift it as clarified
below.
As may be seen again in FIG 1 the two branches of the Chain
which wind partially around each pulley 22, 23 are directed
upwards to reach a respective upper pulley 25, 26, 27, 28
each.
The branches which wind on the innermost pulleys 26, 27
descend to join in a central pulley 29 arranged beneath the
table 11 and fastened to the floor. The pulley 28 is
powered by a motor 30.
The branches of the pulleys 22, 23 are directed towards the
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outermost pulleys 25, 28 and wind around them and are
fastened to the upper frame of the station opposite an
anchorage 31, 32. Between the pulleys 25, 28 and the
connection 31, 32 the chains form a loop in which is hung a
5 pulley 33, 34 to which is hung a counterweight 35, 36. The
counterweight pulleys are near an appropriate upper striker
37, 38 on which they can be supported alternately by means
of their brackets 42, 32 as clarified below.
Basically, each chain defines two main branches 39, 40
extending from the rocking board to the frame above them to
lift one end or the other of the board depending on the
direction of rotation of the motor. The two main branches
of each chain are arranged symmetrically to a median plane
41 transversal to the board. The motor is advantageously
located near this transversal plane.
By appropriately operating the motor 30 the chain is made
to run to the right or left so that the main branch respec-
tively to the left or right of the powered pulley 29
becomes shorter or longer while the opposite branch is held
in tension by its counterweight. Thus, the table 11 is
lifted at one end while it rotates on a pin around the
opposite floor support. This is shown as an example in
FIG°4 for a counterclockwise rotation of the powered
pulley. The pulley of the counterweight on the board part
which rises goes to rest against the respective upper
striker 37 or 38. A rotation in the opposite direction
would of course cause specular movement of the board. A
continuous alternating rocking movement can be readily
achieved with a continuous timed reversal of the motor
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movement.
It is now clear that the predetermined purposes have been
achieved by making available a station with very simple
mechanics and small in size (in particular with minimal
clearance between the board level and the floor) allowing
rocking of a support table onto which are fed support
boards.
In addition to the advantage of a single power source and
the absence of other mechanisms such as for example the
prior art bolts for the tilting movement on one side or the
other, the station in accordance with the present invention
also has the advantage of supplying partial load balancing
because during the rise of one end the active counterweight
(which descends) is the one on the opposite end and the
counterweight on the rising end is located permanently at
the top.
In addition, all the mechanical parts are arranged outside
the rocking board viz outside the zone where the liquids
can drip and excellent inspectability, accessibility and
maintainability are achieved.
Naturally the above description of an embodiment applying
the innovative principles of the present invention is given
by way of non-limiting example of said principles within
the scope of the exclusive right claimed here. For example
the chain path can be different from that shown and the
motor can be positioned opposite other idling pulleys. In
particular, the powered pulley 29 can be arranged in the
station ceiling by exchanging the positions of the pulleys
18, 19 and 26, 27.
